The present invention relates to a bottle opening machine for removing crown caps from the head parts of bottles contained in a bottle case and more particularly to an improved bottle opening machine in which the crown caps are continuously and automatically removed from the opening rims of the bottles in the bottle case as it is conveyed on a conveyance system.
As is well known, beer, refreshing drink or the like filled in bottles are delivered from a bottling factory to a consumer market and after the consumers enjoy them the empty bottles are recovered for bottling beer, refreshing drink or the like again. It is often found that among the recovered empty bottles (as contained in the bottle case) some ones are manually capped with crown caps. This causes necessity for removing these caps from the bottles in a preliminary process before they are transferred to a bottling line in the bottling factory.
A hitherto known bottling machine is generally constructed such that cap removing operation is practiced by way of the steps of lowering a pair of pawl means to the position corresponding to the lip portion of the crown cap to be removed, allowing the pair of pawl means to be actuated until they are engaged to the lip portion and then forcibly raising up the crown cap while they hold the latter therebetween.
On the other hand, a bottle opening machine of the type including cap removing parts adapted to carry out a circular movement is disclosed in Japanese Laid-Open Patent No. 17,983/77 (corresponding to Japanese Patent Application No. 93,529/55). Specifically, the conventional bottle opening machine is constructed such that each cap removing part turns its circular movement to a linear movement at the cap removing area. That is, its cap removing operation is practiced by the steps of lowering a pair of pawl means displaceably held on the cap removing part until they are engaged to the lip portion of the crown cap, and forcibly raising up the crown cap while they hold the cap therebetween with the opening rim of the bottle depressed so as to prevent the latter from being lifted above the bottle case.
However, it is pointed out as a drawback with respect to the above-described conventional bottle opening machine that the cap removing operation requires a large amount of power consumption due to the arrangement that the pair of pawl means are raised up while the bottle neck is depressed by means of a retainer and there is a fear of causing damage or chipping on the bottle neck while the crown cap is raised up together with the pair of pawl means engaged thereto.
Another drawback inherent to the conventional bottle opening machine is that due to the upward and downward movements of the pawl means, the pawl means stop at both the upper and lower dead points, accordingly, the cap removing operation is intermittently practiced. That causes a low efficiency for removing the crown caps. Still another drawback is that to prevent the bottle from being lifted above the bottle case while cap removing is effected by means of the pair of pawls in the cap removing part, there is a necessity for a bottle neck retainer and thereby the bottle opening machine becomes incomplicated, resulting in an increased manufacturing cost.